B Could a brown dwarf passing through our solar system ignite Jupiter?

[Drakkith]

But, what if it were back-lit by the sun? I think that's what the majority of believers seem to be saying. That we can't see it because its, from Earth's perspective, in what would be equivalent to the new moon phase.

It can't be back-lit because it's further away from us than the Sun (assuming its coming from the outer solar system). It would need to get between us and the Sun, and at that distance it would be horribly obvious. We're talking massive disruptions in the orbits of the inner planets and, when the dwarf was not in a direct line between the Sun and us, which would be most of the time since it would be moving faster in any orbit than we are, it would be extremely bright (just talking about reflected light here). You would be able to see it in the daytime quite easily.

Again, I explain my behavior, and apologize, in my previous post.

Thank you.

 

[Beth Doodle]

You added a lot of extra sub-questions to the periphery that have distracted from this core question. The answer is relatively straightforward and can be gleaned from looking into the collision of comet Shoemaker-Levy 9 with Jupiter (Google for photos).

The collision was energetic, generating large balls of hot gas that were unfortunately termed "fireballs" (they were not on fire).

A collision between Jupiter and a larger gaseous body would be like that except much bigger. It would be a spectacular sight, lighting-up the daytime sky.

But unless some debris headed for Earth, it would have little lasting effect. Our orbit would wobble a bit less and our tides would smooth a little.

Also, FYI, the asteroid belt is pretty thin and has a small total mass, so a disruption of it wouldn't have much of an effect either.

[Edit] Hmm..., actually, a quick calc tells me the impact would release as much energy as the sun emits in 800 years. That would be enough to cause problems on Earth. Can someone check my math:
Sun output: 3.9x10^26 watts
Jupiter mass: 2x10^27 kg
Assume Jupiter hits it at 100kps.

At last! The drama I crave!

Just kidding! I do have to admit that this is more like what I would expect, from my layman's level of understanding.

I know that the direction of my questions changed and I wound up asking more later, but that's the nature of discussions. I had a number of question to ask but felt it was better to start off with one question, and then go from there. I knew the answers I received would steer me to the next questions I would want to have answered.

The problem is that there isn't a cut-and-dried answer. The details of what happen depend on the exact conditions of the event. A direct impact of a brown dwarf with Jupiter will be different from a near miss, which will be different from a slightly-less-near miss. The mass of the brown dwarf, its speed, trajectory, and a few other properties will also change things. If the event happened on a Tuesday we could end up with a major impact event on Earth, whereas if it happened a day later we might not even have a near-miss from the asteroid.

I started off the conversation with whether an impact could trigger an explosion, but I knew that I would need to ask follow-up questions, depending on what I was told. I was basically planning on presenting other what-if scenarios as the discussion progressed. That's why, after you persuaded me that a miss was more likely, I went on to ask about that.

Common sense starts to fail you when you start talking about uncommon situations that people don't usually experience or talk about. Astrophysics is one of these. Common sense would tell most people that you have to dodge and weave when going through the asteroid belt to avoid hitting an asteroid. But common sense is wrong here, as the average distance between asteroids is miles and miles and miles. You would be hard pressed to even see one as anything more than a small dot in the distance.

Actually, I'm going by more than just common sense. I do have a modicum of knowledge about astrophysics gleaned from years of watching Discovery Channel type TV shows. I know just enough to be dangerous. That's why I say I expected something more dramatic. I know about the mass of Jupiter and how that mass affects the orbits of every other object in the solar system. I already expected someone to mention the orbits shifting, although I didn't know how much of a shift there might be. I was however also interested in the other effects that I didn't know about - like how big the visual impact would be and whether or not it would cause impacts events on earth.

Also note that I don't know exactly what you mean by "spectacular" and "non-event". I have to go on my own guess of what you mean based on my understanding of those words and the situation. Would you be able to see it with the naked eye? Almost certainly. Will it look like the special effects from a sci-fi movie? Probably not. At best, a straight up collision would result in a bright source of light in the sky, probably easily outshining the Moon for a short period of time. If that's "spectacular", then I guess it's a spectacular event. A near-miss that tears the planet apart may still shine brightly, but I do not know the exact details of what it would look like.

Yes, I would count that as spectacular. And that is pretty much what I thought might happen. I just wanted to verify it and find out the extent and scope of the brightness - would it be just a bright point of light, or would it appear to us here on Earth as a larger glowing object and, if so, how large?

I brought up non-event because at that point in the discussion I had been told that there would be only a slight brightening that would take a telescope to see and that nothing much else would happen, except for the orbit shifts.

I would disagree with that person, but I also haven't done the math to see how close a brown dwarf would need to be to tear Jupiter apart.

No, you were quite right to disagree with them. I asked this question on an astronomy forum, but that person must have not really belonged there because they said that since Jupiter was a gas giant and therefor didn't have any solid ground (their word, not mine) then it can't be torn apart. After I explained to them about what mass was, just how much of it Jupiter had, etc. their original post suddenly disappeared.

 

[Janus]

I guess because I am feeling frustrated.

I thought that this would be a cut-and-dried answer. When the brown dwarf reached Jupiter, such-and-such will happen. Then, after such-and-such a time, this will happen. To those who are watching from earth, they will see such-and-such in the sky. The long-term effects of this on Earth and the rest of the solar system would be such-and-such.

The problem is that too much depends on the actual circumstances of the encounter. For example, if we assume that a brown dwarf passes by Jupiter close enough for Jupiter to come within its Roche limit, there are a number a factors to consider. How fast are their relative speeds? How much more massive is the Brown dwarf than Jupiter? These two have a lot to do with the outcome. They both determine how long Jupiter remains close enough to the brown dwarf to stay inside the Roche limit. A lower relative velocity means they stay close together longer, and a more massive brown dwarf extends the size of the Roche limit so that Jupiter remains inside of it for a longer time.
If the brown dwarf is not very massive and moving quickly, it won't spend long in the vicinity of Jupiter. And while Jupiter will pull apart for the time when the tidal forces are strong enough, once the brown dwarf has passed by, the mutual gravity of its spread out matter will begin to exert itself and try to pull it back together again. Whether or not it is successful or not depends upon how much energy the tidal forces where able to impart to Jupiter. If the spreading material has reached escape velocity, it will continue to spread out, if it hasn't, it will collect back together.
If the brown dwarf is massive and slow, it will have a longer period in which to pull Jupiter apart and there is a greater chance that it will stay pulled apart.

 

[Beth Doodle]

If there really was another very large body in the solar system, it would have (as Jupiter does), a significant effect on the orbital dynamics of smaller planets.
It should also cause (as Jupiter does), a slight 'wobble' of the Sun.
However we don't see anything peculiar happening.
Also Jupiter is often a very bright object in the sky and has been noted ever since anything in the sky was noted.
Yet somehow an even bigger object is proposed to exist, of which there is no historical record at all?

I really wasn't planning on talking about this Niburu stuff beyond the setup for my question. I didn't want to go off into a conspiracy theory on a science forum, but since you ask, I'll explain it briefly. But, bear in mind that I have not memorized all the intricacies of this Niburu stuff because I wasn't one of the rabid followers. My interest was only because the whole thing fascinated me because the very suggestion that it might be true brought all sorts of colorful scenarios to mind. Big scifi fan here.

So, to the best of my recollection, the basic theory goes something like this.

Niburu/Nemisis/Wormwood/Planet X/etc. is our binary companion with an orbit of about 3,600 years. We are now supposed to be at the point where it has already entered and is currently somewhere nearby. How nearby depends on who is doing the talking. It varies from around Jupiter's orbit (hence the collision question) to almost here to Earth's orbit, which is why some are expecting a collision or near-miss with earth. There is supposed to be all sorts of historical evidence here on Earth of its previous passages through the inner solar system, but we don't need to go into that. Besides I can't recall the details anyway.

What I can recall about why we are not supposed to be able to see it is that for a good amount of time it's approach was from an extreme southern point of view. They said that it was only visible from the Antarctic for a very long time as it approached from behind the sun, from our point of view. That's the source of all sorts of conspiracy theories of the governments having bases there observing it but hiding the truth from the public. But now I guess it's supposed to be between the Earth and the sun - which is why they are all saying that it can't be seen now (back-lit), unless you use an infrared telescope.

I really can't go into much more detail than that because I just don't remember and I'd have to research it, and I'd rather not waste my time doing that, so please don't ask me for more info.

It can't be back-lit because it's further away from us than the Sun (assuming its coming from the outer solar system). It would need to get between us and the Sun, and at that distance it would be horribly obvious. We're talking massive disruptions in the orbits of the inner planets and, when the dwarf was not in a direct line between the Sun and us, which would be most of the time since it would be moving faster in any orbit than we are, it would be extremely bright (just talking about reflected light here). You would be able to see it in the daytime quite easily.

See back-lit above.

 

[Beth Doodle]

The problem is that too much depends on the actual circumstances of the encounter. For example, if we assume that a brown dwarf passes by Jupiter close enough for Jupiter to come within its Roche limit, there are a number a factors to consider. How fast are their relative speeds? How much more massive is the Brown dwarf than Jupiter? These two have a lot to do with the outcome. They both determine how long Jupiter remains close enough to the brown dwarf to stay inside the Roche limit. A lower relative velocity means they stay close together longer, and a more massive brown dwarf extends the size of the Roche limit so that Jupiter remains inside of it for a longer time.
If the brown dwarf is not very massive and moving quickly, it won't spend long in the vicinity of Jupiter. And while Jupiter will pull apart for the time when the tidal forces are strong enough, once the brown dwarf has passed by, the mutual gravity of its spread out matter will begin to exert itself and try to pull it back together again. Whether or not it is successful or not depends upon how much energy the tidal forces where able to impart to Jupiter. If the spreading material has reached escape velocity, it will continue to spread out, if it hasn't, it will collect back together.
If the brown dwarf is massive and slow, it will have a longer period in which to pull Jupiter apart and there is a greater chance that it will stay pulled apart.

I know that people say they know the answers to the questions of this thing's mass, but I don't remember what that's supposed to be.

As far as it's velocity, all I can recall is that it is supposed to be in a 3,600 year orbit, if that helps. What the exact orbit is and what the path within the inner solar system is supposed to be varies. As I stated in my previous post, some think that there will be a direct impact with Jupiter (hence my original question), some think it will be a near pass to Jupiter. Other think there will be an impact with earth, but I think they are thinking more along the lines of a near pass with any impact being with either a planetary body or moon in orbit around the brown dwarf, or with a lot of iron oxide rich debris it's supposed to be dragging around with it.

Now please guys - no more questions about this, I'm not really comfortable talking about any more detail on this Niburu stuff on this science forum, My question and the answers I am seeking are based on science. I only brought Niburu up in the first place because it was the the basis of my original question. I only added the referral to Niburu because I knew that if I were ask my question without that reference, people would ask for it anyway. They'd want to know why I was asking about a brown dwarf impacting with Jupiter.

This is a science forum so I think we should stick to science from here on in. Okay?

 

[davenn]

What I can recall about why we are not supposed to be able to see it is that for a good amount of time it's approach was from an extreme southern point of view. They said that it was only visible from the Antarctic for a very long time as it approached from behind the sun, from our point of view. That's the source of all sorts of conspiracy theories of the governments having bases there observing it but hiding the truth from the public. But now I guess it's supposed to be between the Earth and the sun - which is why they are all saying that it can't be seen now (back-lit), unless you use an infrared telescope.

Honestly, Beth, Me being an astronomer of over 40 years, I can say "this is all total garbage"
From Sydney, Australia, I see all the same nite sky as anyone in Antarctica does
you really need to give this up

As Drakkith and rootone have said, any other significant sized object mass and physical size would have VERY NOTICEABLE effects on the other planetsDave

 

[Beth Doodle]

The issue here is that we've been lenient with our rule against crackpot content: we generally don't allow it even for the purpose of debunking. We're discussing how to handle it, but in the meantime you can help by asking more concise/focused questions without all of the crackpot background behind them. It would also help to recognize that some of these crackpot claims you are trying to debunk are practically insane, which makes it hard to give a straight/no frills response. In other words, you are trying to generate "legitimate science questions" and not having much luck. Sometimes you just have to accept that no matter how much lipstick you put on it, we can still see the pig.

Sorry, but there have been so many posts that I've wound up cross-posting while not being aware that others have posted since the last post I was aware of. That's why I missed this post until now.

As you can see from my last two posts, I answered the questions that I was asked about Niburu, but I did say that I din't want to discuss it any further. And I won't. I want to stick to the science, not go off into the crackpot stuff.

 

[Beth Doodle]

Honestly, Beth, Me being an astronomer of over 40 years, I can say "this is all total garbage"
From Sydney, Australia, I see all the same nite sky as anyone in Antarctica does
you really need to give this up

As Drakkith and rootone have said, any other significant sized object mass and physical size would have VERY NOTICEABLE effects on the other planetsDave

Everyone has been cross-posting so things have gotten a bit messy but if you read my last few posts you will see that I am not a proponent for the theory. And it's the policy of this forum to not go into this sort of stuff. So I apologize for not commenting on the content of your post, but we can no longer continue discussing anything pertaining to this subject except for the hypothetical nature of the collision itself. By that, I mean the science of it.

Think of it as if I were an author researching this collision scenario for a movie I was writing. Anyone with any science background knows that movies don't necessarily stick to what is in the realm of reality. The drama is what counts, so they bend reality and science to suit their desires - reality need not apply. So son't dwell on the legitimacy of the existence of this thing - it's not really worthy of wasting your time on. Just stick to the science. Thanks!

 

[davenn]

Anyone with any science background knows that movies don't necessarily stick to what is in the realm of reality. The drama is what counts, so they bend reality and science to suit their desires - reality need not apply.

Sorry, but this is a science forum ... reality MUST apply

Just stick to the science. Thanks!

and everyone has been doing their best to give you credible science based answers, despite your constant strolling into fiction Dave

 

[Beth Doodle]

The visibility of a Brown dwarf depends on its size and age. Only very old ones will have cooled enough to emit no visible light. Brown dwarfs have spectral types just like main sequence stars: L and T with a provisional class Y. Even the ultra cool brown dwarf UGPS 0722-05 which is a possible candidate as a class Y would, at the distance of Jupiter from Earth, have an apparent magnitude brighter than the brightest star, and would be quite visible.

Because of the amount of cross-posting going on, this is another post I missed until going back and reviewing the entire thread, so I apologize for not responding sooner.

I was going by what I read on Wikipedia about the visibility of brown dwarfs which is this:

"Early theories concerning the nature of the lowest-mass stars and the hydrogen-burning limit suggested that a population I object with a mass less than 0.07 solar masses (M☉) or a population II object less than 0.09 M☉ would never go through normal stellar evolution and would become a completely degenerate star.[12] The first self-consistent calculation of the hydrogen-burning minimum mass confirmed a value between 0.08 and 0.07 solar masses for population I objects.[13][14] The discovery of deuterium burning down to 0.012 solar masses and the impact of dust formation in the cool outer atmospheres of brown dwarfs in the late 1980s brought these theories into question. However, such objects were hard to find as they emit almost no visible light. Their strongest emissions are in the infrared (IR) spectrum, and ground-based IR detectors were too imprecise at that time to readily identify any brown dwarfs."

Also, I was going on the assumption that this thing could be undetectable by the naked eye from Earth because it could be between the sun and earth, and therefore back-lit.

But, hold on, just this minute it occurred to me that that can't happen if it's out near Jupiter. If Jupiter, which gives off no light of it's own, is visible to us from earth, then this object, no matter how much light it did or did not emit, would be visible too.

Actually, this sudden epiphany explains a lot to me. It doesn't explain the question of what exactly would happen in the case of a collision or near miss, but it does bring to light (no pun intended) that we'd see this thing coming from a long way off if it were there. As long as Jupiter were visible from earth, then so would this thing be visible if it were in it's vicinity.

Interesting.

I need to re-read all the posts and think on this a bit, but I think all you fine folks may have given me all the answers that I need. Even though as some of you have said, the results would vary depending on the particular circumstances of the orbits involved. But I think I have enough of the puzzle pieces now that give me all that I need to know.

I want to thank you all for your time and insights into this. I really do appreciate it!

 

[berkeman]

Beth has asked that the thread remain closed now. Thank you everybody for you help on her questions.